CN114783280A

CN114783280A - Backboard and display device

Info

Publication number: CN114783280A
Application number: CN202210071419.0A
Authority: CN
Inventors: 闵明安
Original assignee: Samsung Display Co Ltd
Current assignee: Samsung Display Co Ltd
Priority date: 2021-01-22
Filing date: 2022-01-21
Publication date: 2022-07-22
Also published as: US20220238049A1; US11915625B2; KR20220106888A

Abstract

A back panel and a display device are provided. The display device includes: a display panel; and a back panel on a rear side of the display panel and including a first folding region configured to be folded in a first direction and a second folding region intersecting the first folding region and configured to be folded in a second direction intersecting the first direction.

Description

Backboard and display device

Technical Field

Aspects of some embodiments of the present disclosure relate to a backplane and a display device.

Background

Various electronic devices such as a mobile phone, a tablet computer, a multimedia player, or a television have been used, and a Liquid Crystal Display (LCD) or an Organic Light Emitting Display (OLED) is applied thereto as a display device.

Recently, various types of display devices have been developed. For example, flexible display devices are being developed that can be bent, folded, or wrapped in a curved manner to allow a wide range of control over shapes and sizes. A flexible substrate used in a flexible display device may be very thin so that a back plate for supporting the flexible substrate may be positioned at the bottom of the flexible substrate. However, when the display device is repeatedly folded and unfolded, the plastic deformation of the back sheet and/or the flexible substrate may not allow the display device to be restored to a proper or desired shape, and a large amount of stress may be applied to the back sheet.

The above information disclosed in this background section is only for enhancement of understanding of the background, and therefore the information discussed in this background section does not necessarily constitute prior art.

Disclosure of Invention

Aspects of some embodiments of the invention may include a back panel and a display device that may be folded or unfolded with relative ease in at least two directions.

According to some embodiments of the invention, a display device includes: a display panel; and a back panel on a rear side of the display panel and including a first folding region configured to be folded in a first direction, and a second folding region intersecting the first folding region and configured to be folded in a second direction intersecting the first direction.

According to some embodiments, the first folding region may include a plurality of first holes, and a length of each of the plurality of first holes in the first direction is smaller than a length of each of the first holes in the second direction in a plan view.

According to some embodiments, the plurality of first holes may have a first length in the first direction and may have a second length in the second direction, and the first length may be less than the second length.

According to some embodiments, the second folded region may include a plurality of second holes, and a length of each of the second holes in the first direction is greater than a length of each of the second holes in the second direction in a plan view.

According to some embodiments, the plurality of second holes may have a third length in the first direction and may have a fourth length in the second direction, and the third length may be greater than the fourth length.

According to some embodiments, the display panel may include a flexible substrate, and the backplane may have a modulus greater than a modulus of the flexible substrate.

According to some embodiments, the first hole may have at least one of a rectangular shape, a diamond shape, an oval shape, and a square shape, a long side of the rectangular shape being parallel to the second direction, a long axis of the diamond shape being parallel to the second direction, and a long axis of the oval shape being parallel to the second direction.

According to some embodiments, the second hole may have at least one of a rectangular shape, a diamond shape, an oval shape, and a square shape, a long side of the rectangular shape being parallel to the first direction, a long axis of the diamond shape being parallel to the first direction, and a long axis of the oval shape being parallel to the first direction.

According to some embodiments, the backsheet may further comprise a third fold region, and the third fold region may comprise a region where the first fold region overlaps the second fold region.

According to some embodiments, in a plan view, a length of the third folded region in the first direction may be greater than the first length, and a length of the third folded region in the second direction may be greater than the fourth length.

According to some embodiments, the third folded region may include a plurality of third holes, a length of each of the third holes in the first direction is greater than a length of each of the third holes in the second direction in a plan view, and the plurality of third holes may have a first length in the first direction and may have a fourth length in the second direction.

According to some embodiments, the third folded region may include a plurality of third holes, a length of each of the third holes in the first direction is smaller than a length of each of the third holes in the second direction in a plan view, and the plurality of third holes may have a first length in the first direction and may have a fourth length in the second direction.

According to some embodiments, the third folded region may include a plurality of third holes, a length of each of the third holes in the first direction is the same as a length of each of the third holes in the second direction in a plan view, and the plurality of third holes may have a first length in the first direction and may have a fourth length in the second direction.

According to some embodiments, the third folded region may be made of at least one of Polyurethane (PU), Thermoplastic Polyurethane (TPU), polyacrylate, rubber, and silicon.

According to some embodiments, the third fold region may be manufactured by at least one of injection molding, extrusion molding, vacuum forming, and cast molding.

According to some embodiments, the back plate may further include a step compensation member for filling the third hole.

According to some embodiments, the step compensation member may be made of at least one of Polyurethane (PU), Thermoplastic Polyurethane (TPU), polyacrylate, and rubber.

According to some embodiments, the plurality of third holes may penetrate the back plate in a thickness direction of the back plate.

According to some embodiments, the plurality of third holes may be positioned at least one of an upper side and a lower side of the back plate, and a depth of the third holes may be less than a depth of the back plate.

According to some embodiments of the invention, a backplane comprises: a first fold region that folds in a first direction; a second folding region that intersects the first folding region and is folded in a second direction that intersects the first direction; and a third folding region in which the first folding region overlaps the second folding region, wherein the first folding region may include a plurality of first holes each having a length in the first direction smaller than a length in the second direction of each of the first holes in a plan view, the plurality of first holes having a first length in the first direction and may have a second length in the second direction, the first length may be smaller than the second length, the second folding region may include a plurality of second holes each having a length in the first direction larger than a length in the second direction of each of the second holes in a plan view, the plurality of second holes may have a third length in the first direction and may have a fourth length in the second direction, the third length may be greater than the fourth length, the third folded region may include a plurality of third holes, a length of each of the third holes in the first direction is the same as a length of each of the third holes in the second direction in a plan view, and the plurality of third holes may have the first length in the first direction and may have the fourth length in the second direction.

According to some embodiments of the present disclosure, the display device may be folded and unfolded relatively easily.

According to some embodiments of the present disclosure, the durability of the display device may be relatively improved.

Drawings

Fig. 1 illustrates a perspective view of a display device according to some embodiments of the present disclosure.

Fig. 2 shows a cross-sectional view of the display device with respect to line I-I' of fig. 1.

Fig. 3 shows a cross-sectional view of the display device with respect to line II-II' of fig. 1.

Fig. 4 illustrates a top plan view of a backplane of a display device and an enlarged portion of a region of the backplane, according to some embodiments of the present disclosure.

Fig. 5A-5D show top plan views of examples of patterns positioned in the overlap region of the backplane of fig. 4.

Fig. 6A to 6D show separate cross-sectional views of an overlapping region in a display device, in which the holes positioned in the back plate are arranged in a pattern according to fig. 5A.

Fig. 7 illustrates a top plan view of a backplane of a display device according to some embodiments of the present disclosure.

Detailed Description

Aspects of some embodiments of the present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which aspects of some embodiments of the invention are shown. As those skilled in the art will appreciate, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of embodiments in accordance with the invention.

Descriptions of some components or parts that may not be necessary to enable a person of ordinary skill in the art to make, use, and understand aspects of embodiments in accordance with the present invention may be omitted, and like reference numerals may be used to refer to like elements in different embodiments throughout the specification.

For better understanding and ease of description, the size and thickness of each configuration shown in the drawings are arbitrarily illustrated, but the present invention is not limited thereto. In the drawings, the thickness of layers, films, panels, regions, etc. are exaggerated for clarity. The thickness of some layers and some regions are exaggerated for illustrative purposes.

It will be understood that when an element such as a layer, film, region or substrate is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present. The words "on … …" or "above … …" mean positioned on or under the subject portion, but do not necessarily mean positioned on the upper side of the subject portion based on the direction of gravity.

Unless explicitly described to the contrary, the word "comprise" and variations such as "comprises" or "comprising," will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

The terms "x-axis direction", "y-axis direction", and "z-axis direction" are used, and here, "x-axis direction" is a first direction, "y-axis direction" is a second direction perpendicular to the first direction, and "z-axis direction" is a third direction perpendicular to the first direction and the second direction. The first direction (x-axis direction), the second direction (y-axis direction), and the third direction (z-axis direction) may correspond to a horizontal direction, a vertical direction, and a thickness direction of the display device, respectively.

The phrase "in a plan view" indicates that the object portion is viewed from the top, and the phrase "in a sectional view" indicates that the object portion is viewed from the side in a vertically-cut section.

The display device 10 may include a display panel 110 for receiving a data signal and displaying an image.

When the display device 10 is unfolded, the display panel 110 may include a display area DA for displaying an image, and a non-display area NDA positioned at an edge of the display area DA (e.g., around the periphery or outside of a footprint of the display area DA) where no image is displayed. That is, the non-display area NDA may operate as a bezel area. The display area DA may face the front surface of the display device 10, and may display an image. A specific signal line or driving circuit for applying a signal to the display area DA may be located in the non-display area NDA.

Referring to fig. 1, the display area DA is illustrated as having a rectangular shape, but according to various embodiments, the display area DA may have a rectangular shape with rounded corners, and/or the display area DA may have various other shapes such as a square, a polygon other than a rectangle and a square, a circle, or an ellipse.

The display panel 110 of the display device 10 according to some embodiments may include a plurality of folding regions. Display panel 110 may be folded along fold lines FL1 and FL 2. When the display panel 110 is folded, the display panel 110 may not be folded to have a specific angle on a folding line (e.g., a set or predetermined folding line), but may be folded with a curvature (e.g., a set or predetermined curvature) such that the folded region is positioned at a set or predetermined portion or position of the display panel 110. That is, when the display panel 110 is folded with respect to the folding line FL1, the folded area FA1 may be bent at a corresponding position with a curvature (e.g., a set or predetermined curvature). When the display panel 110 is folded with respect to the folding line FL2, the folding area FA2 may be bent at a corresponding position with a curvature (e.g., a set or predetermined curvature).

The plurality of folding areas may include first and second folding areas FA1 and FA 2. The first folding area FA1 may be folded along a first folding line FL1, and the second folding area FA2 may be folded along a second folding line FL 2. Referring to fig. 1, the first and second folding areas FA1 and FA2 are illustrated as being positioned at the center of the display panel 110, but the positions of the folding areas FA1 and FA2 are not limited thereto. Further, at least two fold regions may be defined. According to some embodiments, the display panel 110 may include more than two folding regions.

As shown in fig. 1, the display panel 110 may include a first folding area FA1, a second folding area FA2, and a first area 1100a, a second area 1100b, a third area 1100c, and a fourth area 1100d divided by the first folding area FA1 and the second folding area FA 2.

The first and second folding areas FA1 and FA2 may extend in different directions. For example, the first folding region FA1 may extend in a second direction (also referred to as a y-axis direction, a direction of the first folding line FL1, or a column direction), and the second folding region FA2 may extend in a first direction (also referred to as an x-axis direction, a direction of the second folding line FL2, or a row direction) intersecting the second direction. For example, the first direction may be perpendicular to the second direction.

The overlapping area 300 may be an area where the first folding area FA1 overlaps the second folding area FA 2. That is, the first and second folding areas FA1 and FA2 may extend from the overlapping area 300.

The first folding area FA1 of the display panel 110 according to some embodiments may be folded inward such that the display sides of the first and

third regions

1100a and 1100c may face the display sides of the second and

fourth regions

1100b and 1100d along the first folding line FL 1. The first folding region FA1 may also be folded outward such that the display sides of the first and

third regions

1100a and 1100c and the display sides of the second and

fourth regions

1100b and 1100d may face outward along the first folding line FL 1.

The second folding area FA2 of the display panel 110 according to some embodiments may be folded inward such that the display sides of the first and

second regions

1100a and 1100b may face the display sides of the third and

fourth regions

1100c and 1100d along the second folding line FL 2. The second fold region FA2 may be folded outward such that the display sides of the first and

second regions

1100a and 1100b and the display sides of the third and

fourth regions

1100c and 1100d may face outward along the second fold line FL 2.

Fig. 2 illustrates a cross-sectional view of the display device with respect to line I-I' of fig. 1, the cross-sectional view illustrating a stacked structure of the display device.

As shown in fig. 2, the display device 10 includes a cover member 210, a display panel 110, and a back plate 270. Referring to fig. 2, the cross-section of each layer is marked with hatching lines that distinguish the layers and do not show patterns formed on the layers.

The cover member 210 may be positioned on an upper side of the display panel 110 to protect the display panel 110 from external impact. According to some embodiments, the cover member 210 may be attached to the display panel 110 by an adhesive layer.

For example, the cover member 210 may be a member having various functions, such as a touch panel, a polarizer, a window, or a combination thereof.

When the cover member 210 corresponds to the window, the cover member 210 may have a material that is light-transmittable so as to recognize an image generated by the display panel 110 through the cover member 210 from the outside. For example, the cover member 210 may include a glass material, or may include a plastic material such as polymethyl methacrylate (PMMA) resin or Polycarbonate (PC) resin. The cover member 210 may be made in a relatively thin film shape such that the cover member 210 may have a flexible characteristic, i.e., the cover member 210 is easily bent or folded together with the display panel 110.

The display panel 110 may include a substrate 250 and a display element 230 formed on the substrate 250. The display panel 110 may receive a data signal and may display an image.

When the display panel 110 is a flexible display panel, the display panel 110 may be implemented with an Organic Light Emitting Display (OLED), an electrophoretic display, an electrochromic display (ECD), an electrowetting display panel, or a quantum dot display panel.

When the display panel 110 is a flat display panel, the display panel 110 may be implemented using a Liquid Crystal Display (LCD) or a plasma display device (PDP).

For example, when the display panel 110 is a Light Emitting Diode (LED) display panel, the display element 230 may include a Light Emitting Diode (LED) and a thin film transistor for driving the Light Emitting Diode (LED). In this case, a Light Emitting Diode (LED) may include an anode connected to the thin film transistor, an organic emission layer positioned on the anode, and a cathode positioned on the organic emission layer. A barrier film for preventing or reducing permeation of external moisture or other contaminants may also be formed on the Light Emitting Diode (LED).

The substrate 250 may be a flexible substrate comprising a flexible polymer material such as polyimide.

The back plate 270 may support the display panel 110. In an embodiment, the backplane 270 may be on the back side of the display panel 110. The back plate 270 may include a first support region 270a corresponding to the position of the first region 1100a, a second support region 270b corresponding to the position of the second region 1100b, and a region 275 corresponding to the position of the first folding region FA 1. In other words, the first folding area FA1 of the display panel 110 may also be referred to as a first folding area FA1 of the back panel 270, and the second folding area FA2 of the display panel 110 may also be referred to as a second folding area FA2 of the back panel 270.

The back plate 270 may overlap the substrate 250 in a thickness direction, and may be disposed at the bottom of the substrate 250. The back plate 270 may be made of a metal material such as stainless steel (SUS) or aluminum, or a polymer such as Polymethylmethacrylate (PMMA), Polycarbonate (PC), polyvinyl alcohol (PVA), Acrylonitrile Butadiene Styrene (ABS), or polyethylene terephthalate (PET).

The back plate 270 may have a rigidity greater than that of the substrate 250. That is, the back-plate 270 may have a modulus greater than that of the substrate 250. Therefore, when an external force for bending the display device 10 is applied, a force in a direction opposite to the external force is generated by the back plate 270, and the back plate 270 may maintain the display device 10 in a relatively flat state. Therefore, the display device 10 can be made less prone to being bent. Furthermore, once the backplate 270 is bent, the backplate 270 may not easily return to an originally flat state. That is, when the display device 10 is repeatedly folded and unfolded, plastic deformation may occur in the back plate 270 to disable the display device 10 from being restored, and a large amount of stress may be applied to the back plate 270.

To solve this problem, the thickness of the back plate 270 may be reduced, but when the thickness of the back plate 270 is reduced, elastic recovery energy may also be reduced, and recovery takes a relatively long period of time.

According to some embodiments of the present disclosure, holes having various patterns may be formed in the region 275 corresponding to the first folding area FA1 by performing an etching process on the back plate 270. Here, the region 275 having the same width as the first folding area FA1 may be formed. The region 275 having a width greater than the width of the first folded region FA1 may be formed. The hole may be at least one of an opening, a via hole, and a recess portion (recess or hole), and the hole includes a shape that may be formed in the back plate 270 through an etching process, but embodiments according to the present disclosure are not limited thereto.

The apertures may be disposed in the region 275 along a first fold line FL1 (see fig. 1) of the first fold region FA 1. In the region 275, the holes can be arranged at equal intervals, and the shape, size, width, gap, and location between the holes can be modified. For example, the hole may have various shapes such as a rectangular shape, a diamond shape, an oval shape having a constant shortened length, a circular shape, a square shape, or a trapezoidal shape, and the shape of the hole is not limited. The zone 275 (also referred to as the overlap region 301 in fig. 4) will be described in more detail with reference to fig. 4 in a later part of the specification.

According to some embodiments, the holes positioned in the back plate 270 may be filled with a step compensation member having the same height as the back plate 270. The step compensation member may be made of a material having a rigidity less than that of the back plate 270. That is, the step compensation member may have a modulus smaller than that of the back plate 270.

For example, the step compensating member may be made of a resin such as Polyurethane (PU), Thermoplastic Polyurethane (TPU), polyacrylate, or rubber, but is not limited thereto, and the step compensating member may be made of any material that may allow cushioning. For example, the step compensation member may be manufactured by various forming methods such as injection molding, extrusion molding, vacuum molding, or cast molding, and for example, the step compensation member may have a film shape, but is not limited thereto.

The step compensation member may relieve stress applied to the back plate 270 by the folding operation. The step compensation member may prevent the holes from being damaged during the folding of the display device 10, and may additionally provide restoring force to the patterns changed due to the folding process.

As described above, the display device 10 according to some embodiments of the present disclosure includes the cover member 210, the display element 230, the substrate 250, and the back plate 280.

The cover member 210, the display element 230, and the substrate 250 are as described above.

The back plate 280 may include third and

fourth support areas

280a and 280b corresponding to the position of the second folding area FA2, and an area 285 corresponding to the position of the overlapping area 300.

By performing an etching process on the back plate 280, holes may be formed in various patterns in the third and

fourth support areas

280a and 280b corresponding to the second fold area FA 2.

In the third and

fourth support areas

280a, 280b, apertures may be disposed along the fold line FL2 (see fig. 1). The holes may be arranged at equal intervals, and the shape, size, width, gap, and position between the holes may be modifiable. For example, the hole may have various shapes such as a rectangular shape, a diamond shape, an oval shape having a constant shortened length, a circular shape, a square shape, or a trapezoidal shape, and the shape of the hole is not limited.

The region 285 is positioned in the back panel 280 corresponding to the position of the overlap region 300 where the first folding region FA1 (see fig. 1) overlaps the second folding region FA2 in the overlap region 300. The region 285 may have the same area as the overlap region 300, or the region 285 may include the overlap region 300 and may have a larger area than the area of the overlap region 300.

In the region 285, the apertures may be arranged in a pattern that is symmetric with respect to the first fold line FL1 (see fig. 1) and symmetric with respect to the second fold line FL2 (see fig. 1). The holes in the region 285 may have a shape such as a circle, square, or cross, and may have any shape in a direction parallel to the first fold line FL1 and in a direction parallel to the second fold line FL 2. The region 285 (also referred to as an overlap region 301 in fig. 5A to 5D) will be described with reference to fig. 5A to 5D.

Referring to fig. 4, the back sheet may include a first folding area FA1, a second folding area FA2, and a first region 4100a, a second region 4100b, a third region 4100c, and a fourth region 4100d divided by a plurality of folding areas. In an embodiment, the first folded area FA1 may be configured to fold in a first direction (i.e., along the first fold line FL1 shown in fig. 1), and the second folded area FA2 may intersect the first folded area FA1 and be configured to fold in a second direction (i.e., along the second fold line FL2 shown in fig. 1).

A plurality of apertures (also referred to as a plurality of first apertures) may be disposed in the first fold region FA1 along the first fold line FL 1. In a plan view, a length of the plurality of first holes in the first direction may be smaller than a length of the plurality of first holes in the second direction. In an embodiment, the plurality of first holes may have a first length in the first direction and a second length in the second direction, and the first length may be less than the second length. Area 4001 shows an enlarged portion of the first fold area FA 1. As shown in region 4001, the plurality of apertures positioned in the first fold area FA1 may be arranged such that the respective major axes may be positioned parallel to the first fold line FL1 and the minor axes may be positioned parallel to the folding direction of the first fold area FA 1. The plurality of holes may be formed with the same width as the width of the first folding area FA1, or may be formed with a width greater than the width of the first folding area FA 1.

The first folding area FA1 may include a plurality of holes formed as first patterns 4001a positioned in a (2n-1) th column and second patterns 4001b positioned in a2 n-th column, where n is a positive integer (e.g., greater than 0). The first pattern 4001a and the second pattern 4001b are configured to extend in the column direction, respectively. That is, the respective long axes of the first pattern 4001a and the second pattern 4001b may be parallel to the first folding line FL 1.

The first distance D1 between the adjacent first patterns 4001a or the adjacent second patterns 4001b may be equal to the respective first lengths L1 of the first and

second patterns

4001a and 4001b, or may be smaller than the first length L1.

The plurality of holes arranged in the (2n-1) th column as the first pattern 4001a may be positioned between the plurality of holes arranged in the 2 n-th column as the second pattern 4001 b. For example, the centers of the holes arranged as the first pattern 4001a may correspond to the spaces between the holes arranged as the second pattern 4001b, and the centers of the holes arranged as the second pattern 4001b may correspond to the spaces between the holes arranged as the first pattern 4001 a. The holes formed as the first pattern 4001a in the (2n-1) th column may be arranged to correspond to the holes formed as the second pattern 4001b in the 2 n-th column.

The hole may have a shape symmetrical with respect to the direction of the first folding line FL1, but the shape of the hole is not limited thereto. For example, the holes may have a shape such as a rectangle whose longer side is parallel to the direction of the first folding line FL1 in a plan view, or a rhombus whose longer axis is parallel to the direction of the first folding line FL1 in a plan view, an oval shape whose longer axis is parallel to the direction of the first folding line FL1, or a shape such as a circle or a square.

When the display device 10 (see fig. 1) is folded along the first folding line FL1, the repulsive force generated to the folding may be changed according to the gap T1 between the holes. When the display device 10 is folded, the radius of curvature of the display device 10 may be changed by adjusting the arrangement of the holes formed in the back plate as a pattern. Accordingly, stress applied to the display panel 110 (see fig. 1) may be relieved to minimize damage to the display panel 110.

A plurality of apertures (also referred to as a second plurality of apertures) may be disposed in the second fold region FA2 along the fold line FL 2. In a plan view, a length of each second hole in the first direction may be greater than a length of each second hole in the second direction. In an embodiment, the plurality of second holes may have a third length in the first direction and a fourth length in the second direction, and the third length may be greater than the fourth length. Area 4002 shows an enlarged portion of second fold area FA 2. As shown in region 4002, the plurality of apertures positioned in the second fold area FA2 may be arranged such that the respective major axes may be positioned parallel to the second fold line FL2 and the minor axes may be positioned parallel to the folding direction of the second fold area FA 2. The plurality of holes may be disposed to have the same width as the second folding area FA2, or may be disposed to have a width greater than that of the second folding area FA 2.

The second folding area FA2 may include a plurality of holes formed as a first pattern 4002a positioned in the (2n-1) th row and a second pattern 4002b positioned in the 2 n-th row, where n is a positive integer (e.g., greater than 0). The first pattern 4002a and the second pattern 4002b are configured to extend in a row direction, respectively. That is, the respective major axes of the first pattern 4002a and the second pattern 4002b may be parallel to the second folding line FL 2.

The second distance D2 between the adjacent first patterns 4002a or the adjacent second patterns 4002b may be equal to the respective second lengths L2 of the first patterns 4002a and the second patterns 4002b, or may be smaller than the second length L2.

The plurality of holes arranged in the (2n-1) th row as the first pattern 4002a may be positioned between the plurality of holes arranged in the 2 n-th row as the second pattern 4002 b. For example, the centers of the holes arranged as the first pattern 4002a may correspond to the spaces between the holes arranged as the second pattern 4002b, and the centers of the holes arranged as the second pattern 4002b may correspond to the spaces between the holes arranged as the first pattern 4002 a. The holes arranged as the first pattern 4002a in the (2n-1) th row may be arranged to correspond to the holes arranged as the second pattern 4002b in the 2 n-th row.

The hole may have a shape symmetrical with respect to the direction of the second folding line FL2, but the shape of the hole is not limited thereto. For example, the holes may have a shape such as a rectangle whose longer side is parallel to the direction of the second folding line FL2 in a plan view, or a rhombus whose longer axis is parallel to the direction of the second folding line FL2 in a plan view, an oval shape whose longer axis is parallel to the direction of the second folding line FL2, or a shape such as a circle or a square.

When the display device 10 (see fig. 1) is folded along the second folding line FL2, the repulsive force generated to the folding may be changed according to the gap T2 between the holes. When the display device 10 is folded, the radius of curvature of the display device 10 may be changed by adjusting the arrangement of the holes formed in the back plate as a pattern. Accordingly, stress applied to the display panel 110 (see fig. 1) may be relieved to minimize damage to the display panel 110 or reduce damage to the display panel 110.

A plurality of holes arranged as a third pattern may be formed in an overlap area 301 (also referred to as a "third fold area"), in which the first fold area FA1 overlaps the second fold area FA2 in the overlap area 301. In an embodiment, the third folding area may include a region where the first folding area FA1 overlaps the second folding area FA 2. In a plan view, a length of the third folded region in the first direction may be greater than the first length, and a length of the third folded region in the second direction may be greater than the fourth length. The holes in the overlapping region 301 may have a shape that is symmetrical with respect to the direction of the first folding line FL1 and also with respect to the direction of the second folding line FL 2. The holes in the overlap area 301 will be described in later parts of the present specification with reference to fig. 5A to 5D.

As described above, various patterns may be formed in the overlap region 301 by performing an etching process on the back plate. After forming various patterns in the overlap area 301, the holes positioned in the overlap area 301 may be filled with the step compensation member.

According to some embodiments, the portion of the back plate corresponding to the overlapping region 301 may be made of a resin such as Polyurethane (PU), Thermoplastic Polyurethane (TPU), polyacrylate, or rubber, but is not limited thereto, and the portion may be made of any material for allowing cushioning. Further, the various patterns described above may be formed on this portion. In an embodiment, the third folded region may be made of at least one of Polyurethane (PU), Thermoplastic Polyurethane (TPU), polyacrylate, rubber, and silicon. Fig. 5A to 5D show top plan views of examples of patterns positioned in the overlap area 301 of the back plate of fig. 4. For convenience of description, the holes located in the overlapping region 301 are illustrated in fig. 5A to 5D as being formed or arranged symmetrically with respect to the first folding line FL1 and the second folding line FL2, and the plurality of holes may be arranged symmetrically with respect to any line parallel to the first folding line FL1 and any line parallel to the second folding line FL 2. Further, for convenience of description, only a portion of the pattern for forming the holes in the overlapping area 301 is shown, but the pattern is not limited thereto.

Fig. 5A shows patterns formed in an overlap region 301 of the back plate. As shown in fig. 5A, a plurality of circular-shaped holes may be repeatedly arranged in the overlap region 301 in a plan view. For example, the overlap region 301 may have a pattern in which a first hole 501a, a second hole 501b, a third hole 501c, and a fourth hole 501d are arranged. The first hole 501a, the second hole 501b, the third hole 501c, and the fourth hole 501d may have a circular shape in a plan view. The case where the overlapping area 301 in which a plurality of circular-shaped holes are arranged will be described in more detail below with reference to fig. 6A to 6D.

Fig. 5B shows another example of patterns formed in the overlapping area 301 of the back plate. As shown in fig. 5B, in a plan view, holes of the following shapes may be repeatedly arranged in the overlap region 301: two perpendicular rectangles 502b each having semicircular ends are combined (e.g., intersected) and

circles

502a, 502c, 502d, and 502e are (approximately) arranged at four corners. The first length L11 may be substantially equal to the second length L12.

Fig. 5C shows another example of patterns formed in the overlapping area 301 of the back plate. As shown in fig. 5C, a plurality of square-shaped holes may be repeatedly arranged in the overlap region 301 in a plan view. For example, the overlap region 301 may have a pattern in which a first hole 503a, a second hole 503b, a third hole 503c, and a fourth hole 503d are arranged. The first hole 503a, the second hole 503b, the third hole 503c, and the fourth hole 503d may have a square shape in a plan view.

Fig. 5D shows another example of patterns formed in the overlapping area 301 of the back plate. As shown in fig. 5D, in a plan view, holes of the following shapes may be repeatedly arranged in the overlap region 301: two perpendicular rectangles 504b are combined (e.g., crossed) and

squares

504a, 504c, 504d, and 504e are arranged (approximately) at four corners. The first length L21 may be substantially equal to the second length L22.

That is, as shown in fig. 5A to 5D, the shape of the plurality of holes positioned in the overlap region 301 is modifiable in many ways, and the plurality of holes may be formed in any (or any suitable) pattern that is symmetric with respect to the direction of the first folding line FL1 and also symmetric with respect to the direction of the second folding line FL 2. For example, the shape of the plurality of holes located in the overlap area 301 may be the same (or substantially the same) as the shape of the plurality of holes in the first and second folding areas FA1 and FA2 in fig. 4.

The display device 10 shown in fig. 6A to 6D may include a cover member 210, a display element 230, a substrate 250, and a back plate 670. The cover member 210, the display element 230, and the substrate 250 correspond to the description provided above. Referring to fig. 6A to 6D, the back plate 670 has a thickness T6.

The back plate 670 may have the above-mentioned first hole 501a, second hole 501b, third hole 501c, and fourth hole 501 d.

Fig. 6A shows a display device 10 that includes an aperture positioned in a backplane 670. The hole positioned in the overlap region 301 may penetrate the back plate 670 in the thickness direction of the back plate 670.

Fig. 6B shows a display device 10 that includes holes having a thickness (e.g., a set or predetermined thickness) positioned in the upper and lower sides of a backplane 670. The holes positioned in the overlapping area 301 may not penetrate the back plate 670 in the thickness direction of the back plate 670. The holes positioned in the lower side of the back plate 670 may be positioned corresponding to various positions of the holes positioned in the upper side of the back plate 670. The holes positioned in the upper side of the backplate 670 may have a first thickness T61, and the holes positioned in the lower side of the backplate 670 may have a second thickness T62. The first thickness T61 and the second thickness T62 may be substantially the same or may be different from each other. In this case, the sum of the first thickness T61 and the second thickness T62 is less than the thickness T6.

Fig. 6C shows a display device 10 that includes an aperture having a thickness (e.g., a set or predetermined thickness) positioned in the underside of the backplate 670. The holes positioned in the overlapping area 301 may not penetrate the back plate 670 in the thickness direction of the back plate 670. The hole positioned in the underside of the backplate 670 may have a third thickness T63. The third thickness T63 is less than the thickness T6.

Fig. 6D shows a display device 10 that includes an aperture having a thickness (e.g., a set or predetermined thickness) positioned in the upper side of the backplate 670. The holes positioned in the overlapping area 301 may not penetrate the back plate 670 in the thickness direction of the back plate 670. The hole positioned in the upper side of the back plate 670 may have a fourth thickness T64. The fourth thickness T64 is less than the thickness T6.

As shown in fig. 6A to 6D, holes may be formed in the rear plate 670 by a method suitable for the display device 10. For example, when the display device 10 is folded inward, a hole as shown in fig. 6A or 6C may be formed in the rear plate 670. For example, when the display device 10 is folded outward, a hole as shown in fig. 6A or 6D may be formed in the rear plate 670.

As described above, the holes shown in fig. 6A to 6D may be filled with the step compensation member.

Referring to fig. 7, the back panel may include a first folding area FA1, a second folding area FA2, and a first zone 7100a, a second zone 7100b, a third zone 7100c, and a fourth zone 7100d divided by the first folding area FA1 and the second folding area FA 2.

The first, second, third, and

fourth zones

7100a, 7100b, 7100c, and 7100d are similar to the first, second, third, and

fourth zones

4100a, 4100b, 4100c, and 4100d described above with reference to fig. 4, so some repetitive description thereof may be omitted.

In the first folding area FA1, a plurality of holes may be arranged in the direction of the first folding line FL 1. With respect to the plurality of holes positioned in the first folding area FA1, the respective major axes of the plurality of holes may be positioned parallel to the first folding line FL1, and the minor axes of the plurality of holes may be arranged parallel to the folding direction of the first folding area FA 1. The plurality of holes may be formed with the same width as the width of the first folding area FA1, or the plurality of holes may be formed with a width greater than the width of the first folding area FA 1. The plurality of holes may have a shape symmetrical with respect to the direction of the first folding line FL1, but the shape of the plurality of holes is not limited thereto.

In the second folding region FA2, a plurality of holes may be arranged in the direction of the second folding line FL 2. With respect to the plurality of holes positioned in the second folding area FA2, the respective major axes of the plurality of holes may be positioned parallel to the second folding line FL2, and the minor axes of the plurality of holes may be arranged parallel to the folding direction of the second folding area FA 2. The plurality of holes may be formed with the same width as the width of the second folding area FA2, or may be formed with a width greater than the width of the second folding area FA 2. The plurality of holes may have a shape symmetrical with respect to the direction of the second folding line FL2, but the shape of the plurality of holes is not limited thereto.

The pliable portion 701 (also referred to as a third fold region) may include an overlap region where the first fold region FA1 overlaps the second fold region FA 2. The flexible portion 701 may have a width in the direction of the first folding line FL1 that is greater than the width of the second folding region FA2 in the direction of the first folding line FL1, and may have a width in the direction of the second folding line FL2 that is greater than the width of the first folding region FA1 in the direction of the second folding line FL 2. Referring to fig. 7, the flexible part 701 is illustrated as a quadrangle, and the flexible part 701 may have an arbitrary shape including an overlapping area.

The flexible portion 701 may be made of resin such as Polyurethane (PU), Thermoplastic Polyurethane (TPU), polyacrylate and rubber, silicon (Si), or a combination thereof, but is not limited thereto, and the flexible portion 701 may be made of any material for allowing cushioning and a combination thereof. For example, the flexible portion 701 may be configured with a material manufactured by various forming methods such as injection molding, extrusion molding, vacuum molding, or cast molding.

Holes may not be located in the flexible portion 701. The positioning of the plurality of holes in the flexible portion 701 may be as described above with reference to fig. 4.

In the present invention, the use of all examples or explanatory terms (e.g., etc.) is intended only to describe the invention in detail, and the scope of the invention is not limited by the examples or explanatory terms, unless otherwise claimed. Further, those skilled in the art will recognize that various modifications, combinations, and changes may be configured according to design conditions and factors within the scope of the appended claims or their equivalents.

While the invention has been described in connection with what is presently considered to be practical embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims and their equivalents.

Claims

1. A display device, wherein the display device comprises:

a display panel; and

a back panel on a rear side of the display panel and including a first folding region configured to be folded in a first direction and a second folding region intersecting the first folding region and configured to be folded in a second direction intersecting the first direction.

2. The display device according to claim 1, wherein the first folding region includes a plurality of first holes, and a length of each of the first holes in the first direction is smaller than a length of each of the first holes in the second direction in a plan view.

3. The display device of claim 2, wherein the first plurality of apertures have a first length in the first direction and a second length in the second direction, and the first length is less than the second length.

4. The display device according to claim 3, wherein the second folding region includes a plurality of second holes, and a length of each of the second holes in the first direction is larger than a length of each of the second holes in the second direction in a plan view.

5. The display device of claim 4, wherein the plurality of second holes have a third length in the first direction and a fourth length in the second direction, and the third length is greater than the fourth length.

6. The display device of claim 1, wherein the display panel comprises a flexible substrate, and

the back-sheet has a modulus greater than a modulus of the flexible substrate.

7. The display device of claim 5, wherein the backplane further comprises a third fold region, and

the third fold region includes a region where the first fold region overlaps the second fold region.

8. The display device according to claim 7, wherein a length of the third folded region in the first direction is greater than the first length, and a length of the third folded region in the second direction is greater than the fourth length in a plan view.

9. The display device according to claim 7,

the third fold region is made of rubber and/or silicon.

10. A backsheet, wherein the backsheet comprises:

a first fold region that folds in a first direction;

a second folding region that intersects the first folding region and is folded in a second direction that intersects the first direction; and

a third fold region in which the first fold region overlaps the second fold region,

wherein the first fold region includes a plurality of first holes, a length of each of the first holes in the first direction is smaller than a length of each of the first holes in the second direction in a plan view, the plurality of first holes have a first length in the first direction and a second length in the second direction, and the first length is smaller than the second length,

the second fold region includes a plurality of second holes, a length of each of the second holes in the first direction is greater than a length of each of the second holes in the second direction in a plan view, and the plurality of second holes have a third length in the first direction and a fourth length in the second direction, and the third length is greater than the fourth length, and

the third folded region includes a plurality of third holes, a length of each of the third holes in the first direction is equal to a length of each of the third holes in the second direction in a plan view, and the plurality of third holes have a first length in the first direction and a fourth length in the second direction.